I may give them a go, Matt. I’ve tried all sorts of companies cork gaskets, but they still leak. Did you use sealer or any other thing with them?
It seems you either love 'em or hate 'em, I love mine and have had them for several years. As an experiment I changed one for cork, it didn't leak but it was hard and brittle at the next valve check and I put the silicone back in. They might swell in contact with oil but that just makes them a tighter fit. Expensive compared to cork but unlike cork they can be used time and time again. Cue @Lasty to say how rubbish they are.
The silicone gaskets are absolute tosh ... They MAY be ok if you've repro rocker cover but standard VW have a gap at the top and mine just squeezed out of the gap as the gasket expanded with the heat - along with a large amount of oil ... Sent from my SM-G960F using Tapatalk
If your cylinder heads are flat and have no scratches, your valve covers have flat sealing surfaces and you bail springs are good, then the cork and rubber gaskets will work, provided they are encouraged to lay flat either with sticky sealant or by trimming them so they are not trying to bend up when placed in the covers.. If any of the preceding items is wrong you will have leaks. For most VW aircooled engines built, those cork and rubber gaskets work. The problem with silicone gaskets is that when they are in the presence of oil, some silicones swell up and soften so that a bit of pressure can push them out of the way. The problem with bolt down covers is that the pressure comes from two points, while with the bail spring it is basically all away along the high point of the cover , and in some cases, excessive pressure from the bolts will begin to cause the edges of the cover to start to angle away from the head, so the seal gets worse.
I have minor leaks and am past worrying about it to be honest , part of its 'character' .. Sent from my SM-G960F using Tapatalk
Yes. Leave its spot . I’ve done everything I can possibly do with mine regarding new parts and methods of installation of them, ie covers and gaskets, etc, sealers, no sealers. I’m just wondering if my engine is making excess pressure or not, as all the bearings are new, new rings, etc . The oil level is how the book says, with the correct amount , up to the top mark on the dipstick, but they still drip. No where near as much now, though. So keep an eye on the level as long as it’s between the top and middle line on the dipstick, in theory it should reduce the pressure slightly and not try to find its way out? I would rather the gaps be sealed though. I used the cork gaskets that came with the new covers and springs. I did also think about making some thicker cork gaskets from some floor tiles, using a original as a template by placing the original on top of the thicker tile, and give it a light coating of spray paint in order to get the exact shape, then carefully cutting it out with a scalpel and metal rule.
